Audio apparatus adaptable to user position

ABSTRACT

An audio apparatus adaptable to a user position is provided. The audio apparatus may include a plurality of sub-modules placed at separate locations from one another, each sub-module of the plurality of sub-modules including a loudspeaker configured to generate sound and a communicator configured to perform communication. The first sub-module among the plurality of sub-modules may include a processor that processes an audio signal to be output as sound through the loudspeaker of the first sub-module, determines a user&#39;s position with respect to each of the plurality of sub-modules, and changes a state of the sound being output from the loudspeaker of the first sub-module in accordance with the determined position of the user.

CROSS-REFERENCE TO RELATED THE APPLICATION

This application claims priority from U.S. Provisional Application No.62/256,958 filed on Nov. 18, 2015 in the United States Patent andTrademark Office, the disclosure of which is incorporated herein byreference.

BACKGROUND

1. Field

Apparatuses and methods consistent with the exemplary embodiments relateto an audio apparatus and a computer readable medium, which can processand output an audio signal from various sources to generate a sound ortransmit the audio signal to an external apparatus, and moreparticularly to an audio apparatus and a computer-readable medium thatallow a user to control various devices by the user's voice withoutdirect manual manipulation.

2. Description of the Related Art

To compute and process information in accordance with certain processes,an electronic apparatus typically includes a central processing unit(CPU), a chipset, a memory, and like electronic components forcomputation. Such an electronic apparatus may be classified variously inaccordance with what type of information will be processed therein. Forexample, the electronic apparatus may be classified as an informationprocessing apparatus, such as a personal computer, a server, or the likefor processing general information; an image processing apparatus forprocessing video information; and an audio apparatus for processingaudio information. Such various electronic apparatuses are respectivelyprovided as independent apparatuses to perform their own preassignedfunctions.

Among the electronic apparatuses, the audio apparatus refers to anapparatus capable of processing an audio signal in accordance with audioprocessing methods, and may be achieved in various forms according tothe input/output methods of the audio signal. For example, in terms ofthe input method, the audio apparatus may receive an audio signal froman external apparatus through a communication module or generate anaudio signal based on a sound received from an external environmentthrough the microphone. In terms of the output method, the audioapparatus may output the processed audio signal as a sound through aloudspeaker or transmit the processed audio signal to an externalapparatus through the communication module.

Such an audio apparatus generally provides a specific function as asingle device. For example, a user usually uses audio apparatuses thatspecifically correspond to desired functions such as music playing,control of other devices, messaging, etc. Moreover, if a user wants tofill a space in the user's house with the sound output from an audioapparatus, a home theater or like system needs to undergo a setupprocess. Although an audio apparatus may have a simple structure or beconvenient to use, the performance of the audio apparatus may fall shortof a user's expectations. For instance, a house may not have an openfloor plan and have a complicated shape because of placement of wallsand other structures. Therefore, a single audio apparatus may beinsufficient to fill this space with the sound.

Further, an audio apparatus supporting many functions often has abutton, a touch screen or like interface that requires a user's physicalmanipulation. When the audio apparatus is used at home or at an office,this may be inconvenient for the user because the user has to approachsuch an interface for controlling the audio apparatus.

In this regard, it is desirable if the audio apparatus enables a user toeasily control its various and complicated functions without the user'sdirect touch with the interface.

SUMMARY

According to an aspect of an exemplary embodiment, there is provided anaudio apparatus including a plurality of sub-modules placed at separatelocations from one another, each sub-module including a loudspeakerconfigured to generate sound and a communicator configured to performcommunication. A first sub-module among the plurality of sub-modulesincludes a processor that processes an audio signal to be output assound through the loudspeaker of the first sub-module, determines aposition of a user with respect to each sub-module of the plurality ofsub-modules, and changes a state of the sound being output from theloudspeaker of the first sub-module in accordance with the determinedposition of the user. Thus, the audio apparatus can provide anenvironment optimized for enabling a user to listen to a soundcorresponding to user's position, wherever user is.

The processor may define an area corresponding to positions of theplurality of sub-modules based on distances between the plurality ofsub-modules, and may determine the position of the user with respect tothe defined area. Thus, the audio apparatus determines a user's relativeposition based on a layout of the sub-modules.

The first sub-module may further include a microphone configured toreceive a sound input, and the processor may determine a distancebetween the first sub-module and a second sub-module among the pluralityof sub-modules, based on a time taken by ultrasonic waves being outputfrom the loudspeaker of the first sub-module, reflected from the secondsub-module, and received by the microphone of the first sub-module.Thus, the audio apparatus determines a distance between the sub-modulesin order to determine the layout of the sub-modules.

The processor may receive information about a distance between thesecond sub-module and a third sub-module among the plurality ofsub-modules, from the second sub-module or the third sub-module throughthe communicator of the first sub-module. Thus, information about thedistance between two sub-modules, which cannot be directly determined bythe first sub-module, is obtained, so that the first sub-module candetermine an area formed by the plurality of sub-modules.

The processor may determine the position of the user by determining anangle of the user with respect to each sub-module of the plurality ofsub-modules within the defined area. Thus, the audio apparatusdetermines a user's relative position with respect to the sub-module.

The first sub-modules may include at least two microphones configured toreceive sounds, and the processor may determine the user's positionbased on a phase difference between the sounds respectively received bythe at least two microphones. Thus, the sub-module is able to easilydetermine a user's relative position.

The processor may select one channel of a plurality of channels withinthe audio signal, the selected channel corresponding to the user'sdetermined position. The processor may control a volume level of theselected channel to be different from volume levels of remainingchannels of the plurality of channels. Thus, the audio apparatus canprovide a sound output environment optimized for a user at the user'scurrent position.

The processor may control a volume level of the sound being outputthrough the loudspeaker in accordance with the determined position ofthe user. Thus, the audio apparatus can provide a sound outputenvironment optimized for a user according to the user's currentposition.

The first sub-module may further include a display configured to displayinformation related to the audio signal, and a microphone configured toreceive a sound input. The processor may activate the display and themicrophone if the determined position of the user is closer to the firstsub-module than to the second sub-module, and may deactivate the displayand/or the microphone if the determined position of the user is closerto the second sub-module than to the first sub-module. Thus, the audioapparatus can provide a sub-module control environment optimized for auser at user's current position.

The first sub-module may further include a microphone configured to aspeech from the user. The processor may retrieve contact information ofa call recipient specified by the speech from a mobile phone connectablewith the communicator of the first sub-module, and may dial the callrecipient through the mobile phone. Thus, the audio apparatus enables auser to easily make a phone call by a voice recognition method throughthe sub-module without physically manipulating the mobile phone.

A non-transitory computer-readable medium of an audio apparatus may havea plurality of sub-modules placed at separate locations from oneanother. The non-transitory computer-readable medium may store programcode for a method to be executed by a processor of a first sub-moduleamong the plurality of sub-modules. The method may include processing anaudio signal to be output as sound through a loudspeaker of the firstsub-module, determining a position of a user with respect to eachsub-module of the plurality of sub-modules, and changing a state of thesound being output from the loudspeaker of the first sub-module inaccordance with the determined position of the user. Thus, the audioapparatus can provide an environment optimized for enabling a user tolisten to a sound corresponding to the user's position, wherever theuser is.

The determining the position of the user with respect to each sub-moduleof the plurality of sub-modules may include: defining an areacorresponding to positions of the plurality of sub-modules based ondistances between the plurality of sub-modules; and determining theposition of the user with respect to the defined area. Thus, the audioapparatus determines a user's relative position based on a layout of thesub-modules.

The defining the area corresponding to the positions of the plurality ofsub-modules may include: determining a distance between the firstsub-module and a second sub-module among the plurality of sub-modules,based on a time taken by an ultrasonic wave to be output from theloudspeaker of the first sub-module, reflected from the secondsub-module, and received by a microphone of the first sub-module. Thus,the audio apparatus determines a distance between the sub-modules inorder to determine the layout of the sub-modules.

The defining the area corresponding to the positions of the plurality ofsub-modules may include receiving information about a distance betweenthe second sub-module and a third sub-module among the plurality ofsub-modules, from the second sub-module and/or the third sub-modulethrough a communicator of the first sub-module. Thus, information aboutthe distance between two sub-modules, which cannot be directlydetermined by the first sub-module, is obtained, so that the firstsub-module can determine an area formed by the plurality of sub-modules.

The determining the position of the user with respect to the definedarea may include determining the position of the user by determining anangle of the user with respect to each sub-module of the plurality ofsub-modules within the defined area. Thus, the audio apparatusdetermines a user's relative position with respect to the sub-module.

The determining the angle of the user with respect to each sub-modulemay include determining the position of the user based on a phasedifference between sounds respectively received by at least twomicrophones of the first sub-module. Thus, the sub-module is able toeasily determine a user's relative position.

The changing the state of the sound being output may include: selectingone channel of a plurality of channels within the audio signal, theselected channel corresponding to the determined position of the user;and controlling a volume level of the selected channel to be differentfrom volume levels of remaining channels of the plurality of channels.Thus, the audio apparatus can provide a sound output environmentoptimized for a user at user's current position.

The changing the state of the sound being output may include:controlling a volume level of the sound in accordance with thedetermined position of the user. Thus, the audio apparatus can provide asound output environment optimized for a user at the user's currentposition.

The first sub-module may further include a display configured to displayinformation related to the audio signal, and a microphone configured toreceive a sound input. The method may further include: activating thedisplay and the microphone if the determined position of the user iscloser to the first sub-module than to the second sub-module; anddeactivating the display and/or the microphone if the determinedposition of the user is closer to the second sub-module than to thefirst sub-module. Thus, the audio apparatus can provide a sub-modulecontrol environment optimized for a user at user's current position.

The method may further include: connecting with a mobile phone;retrieving, from the mobile phone, contact information of a callrecipient specified by a speech being input by the user through amicrophone of the first sub-module; and dialing the call recipientthrough the mobile phone. Thus, the audio apparatus enables a user toeasily make a phone call by a voice recognition method through thesub-module without directly manipulating the mobile phone.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become apparent and more readilyappreciated from the following description of exemplary embodiments,taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates an audio apparatus in an installed state according toan exemplary embodiment;

FIG. 2 is a perspective view of a sub-module of an audio apparatus;

FIG. 3 is a perspective view of a structure for mounting a sub-module onan installation surface;

FIG. 4 is a perspective view of another structure for mounting asub-module on an installation surface;

FIG. 5 is a block diagram of signal processing elements in a sub-module;

FIG. 6 is a flowchart of controlling a sub-module in an audio apparatus;

FIG. 7 illustrates a voice field generated by a plurality ofsub-modules;

FIG. 8 illustrates a process of determining a user's position within avoice field by each sub-module in an audio apparatus;

FIG. 9 illustrates sub-modules in an audio apparatus outputting soundsof a stereo channel in accordance with a user's position;

FIG. 10 illustrates sub-modules in an audio apparatus controllingvarious operations in accordance with a user's position;

FIG. 11 is a block diagram illustrating a sound reproduction mode of asub-module in an audio apparatus;

FIG. 12 is a perspective view of a back frame of a sub-module in anaudio apparatus being manipulated by a user;

FIG. 13 is a perspective view of a front frame of a sub-module in anaudio apparatus being manipulated by a user;

FIG. 14 is a block diagram illustrating a process of switching amongcategories of audio data received from an external apparatus;

FIG. 15 is a sequence diagram illustrating a method of a sub-module inan audio apparatus sending a message through a mobile phone;

FIG. 16 is a sequence diagram illustrating a method of a sub-module inan audio apparatus making a phone call through a mobile phone; and

FIG. 17 illustrates a process of a sub-module in an audio apparatuscontrolling an external device through a hub.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Below, exemplary embodiments will be described in detail with referenceto accompanying drawings. The following descriptions of the exemplaryembodiments are made by referring to elements shown in the accompanyingdrawings, in which like numerals refer to like elements havingsubstantively the same functions.

In the description of the exemplary embodiments, an ordinal number usedin terms such as a first element, a second element, etc. is employed fordescribing variety of elements, and the terms are used fordistinguishing between one element and another element. Therefore, themeanings of the elements are not limited by the terms, and the terms arealso used just for explaining the corresponding embodiment withoutlimiting the idea of the invention.

FIG. 1 illustrates an audio apparatus in an installed state according toan exemplary embodiment.

As shown in FIG. 1, an audio apparatus 1 may be installed in variousplaces such as a home, and perform various tasks such as inputting,processing, outputting, etc. with regard to sound. The audio apparatus 1may be supported on a vertical installation surface such as a wall, andoutput a sound frontward in an installed state. However, there are nolimits to the installation position.

In contrast to a conventional audio apparatus provided as a singledevice, the audio apparatus 1 according to an exemplary embodiment mayinclude a plurality of sub-modules 100, 200 and 300. The plurality ofsub-modules 100, 200 and 300 are provided as individual devicesphysically separated from one another, and interwork with one another inindividually processing audio signals.

The plurality of sub-modules 100, 200, and 300 may be installed at anypositions desired by a user, and the installation surfaces are spacedapart by a predetermined distance rather than adjacent to one another.Further, there are no limits to the height at which the sub-modules 100,200 and 300 may be installed. For example, the sub-modules 100, 200 and300 may be installed at a height corresponding to a user's head so thatthe user can easily listen to a sound output from the sub-modules 100,200 and 300 and so that a voice of a user can properly reach thesub-modules 100, 200 and 300.

The audio apparatus 1 may include two or more sub-modules 100, 200 and300. In the example shown in FIG. 1, three sub-modules 100, 200 and 300constitute a set for the audio apparatus 1, but four or more sub-modulesmay constitute one set as well. In this case, each of the sub-modules100, 200 and 300 operates according to the principles of the exemplaryembodiments described herein.

The sub-modules 100, 200 and 300 may connect with a power cable 10 forsupplying power while being supported or mounted on the installationsurface. In addition, the sub-modules 100, 200 and 300 may be providedwith an internal battery for supplying power, thus foregoing the use ofthe power cable 10.

There may be many other ways of supplying power to each of thesub-modules 100, 200 and 300. For example, the sub-modules 100, 200 and300 may each include an independent power generation module thatgenerates power by transforming sunlight or like energy to electricity,or may receive power wirelessly from an external power source. In thecase where the sub-modules 100, 200 and 300 use the batteries, thebattery may be either rechargeable or non-rechargeable. The rechargeablebatteries may be charged by a separate charging device that is separatefrom the sub-modules 100, 200 and 300, or may be charged with powerdirectly supplied to the sub-modules 100, 200 and 300 by a wire orwirelessly.

The plurality of sub-modules 100, 200 and 300, when installed, may sensea user's relative position and respectively process audio signals basedon the sensed position. That is, the audio apparatus 1 according to anexemplary embodiment may include the plurality of sub-modules 100, 200and 300 installed at locations separate from one another, and each ofthe sub-modules 100, 200 and 300 may individually process the audiosignal in accordance with a user's position, thereby providing animproved audio-processing environment for the user.

Below, details of the sub-module 100 will be described. In the audioapparatus 1, the plurality of sub-modules 100, 200 and 300 may includethe same or substantially similar elements, and therefore one sub-module100 will be representatively described in the following exemplaryembodiment.

FIG. 2 is a perspective view of a sub-module of an audio apparatus.

As shown in FIG. 2, the sub-module 100 is shaped like a circular platehaving a predetermined thickness, although the sub-module 100 may have adifferent shape and thickness than what is shown in FIG. 2. Thesub-module 100 includes a back frame 110 arranged in the back of thesub-module 100, and a front frame 120 arranged in the front of thesub-module 100. Various elements for operating the sub-module 100 areaccommodated in an inner space of the sub-module 100 formed by couplingthe back frame 110 and the front frame 120.

The back frame 110 may be shaped like a disc and made of metal orplastic. The space of the sub-module 100 for accommodating variouselements may be formed by the back frame 110. A lateral side of the backframe 110 may have a dial-like structure, so that a user can rotate thelateral wall of the back frame 110.

The front frame 120 may be fitted to the front of the back frame 110,and cover the front of the back frame 110. The lateral side of the frontframe 120 to be fitted to the back frame 110 may be made of metal orplastic. On the other hand, a disc surface 121 of the front frame 120may be made of fabric or textile. The reason why the front frame 120 maybe made of fabric instead of a hard or opaque material will be describedlater.

The fabric surface 121 of the front frame 120 may have various colors.By replacing only the front frame 120 of the sub-module 100, it ispossible to swap in and out a front frame 120 having a color desired bya user to the sub-module 100.

The sub-module 100 may include a display 130 installed on or inside thefront frame 120. The display 130 may have a structure such a liquidcrystal display (LCD) panel for displaying an image or a lesssophisticated display module for displaying a simple text. For example,the display 130 may be a plurality of light emitting diodes (LEDs)arranged in the form of a matrix, and display information ofpredetermined text as each LED is turned on/off.

Inside or on the front frame 120, a loudspeaker, a microphone, etc. aswell as the display 130 may be provided. That is, because the frontframe 120 is made of fabric, a user can not only recognize informationdisplayed on the display 130 but also listen to a sound output from aloudspeaker and input a user's voice to a microphone.

The display 130 may be placed inside the front frame 120, butinformation displayed on the display 130 may be viewable to a userthrough the front frame 120 made of fabric or a screen mesh. That is,light emitted from the LED of the display 130 pass through the surface121 of the front frame 120, so that a user can view the text informationdisplayed on the display 130. Of course, the display 130 is not limitedto the LED, and may have various structures as long as the informationdisplayed on the display 130 may be visible to the user through thefront frame 120.

Similar to the back frame 110, the front frame 120 may have a dialstructure that is rotatable by a user. That is, the sub-module 100 mayhave two dial structures located on the lateral side of the back frame110 and the front frame 120. Each dial structure may be turned by a userto control a function of the sub-module 100. The functions to becontrolled by the dial structure will be described later.

An indicator ring 123 may be installed at the edge of the front frame120 (i.e. around the disc surface 121 made of fabric). The indicatorring 123 may include an LED for generating light of a predeterminedcolor. The indicator ring 123 may control its light emitting state toindicate the current state of the sub-module 100.

For example, the LED of the indicator ring 123 may be activated when thesub-module 100 is turned on, and deactivated when the sub-module 100 isturned off. Further, the indicator ring 123 may be activated when thesub-module 100 makes a sound, and remain inactive when the sub-module100 is not generating any sound. In addition, the indicator ring 123 maybe selectively activated or deactivated corresponding to whether or notthe sub-module 100 enters a voice recognition mode.

A toggle button 125 may be provided in a certain area of the discsurface 121 of the front frame 120, for example, below an areacorresponding to the display 130 of the fabric disc surface 121. Thetoggle button 125 may alternate between an ON state and an OFF statewhenever a user presses the button.

FIG. 3 is a perspective view of a structure for mounting a sub-module100 on an installation surface.

As shown in FIG. 3, a separate support structure may be provided inorder to support the sub-module 100 on the installation surface. Forexample, a bracket 20 may be fastened to the installation surface suchas a wall, and the sub-module 100 may be supported on the bracket 20,thereby allowing the bracket 20 to position the sub-module 100 on theinstallation surface. There may be many ways of fastening the bracket 20to the installation surface. For example, the bracket 20 may be fastenedto the installation surface by a screw or adhered to the installationsurface by an adhesive.

The bracket 20 may include a plate 21 and a rim 23 protruding from thesurface of the plate 21 at a predetermined height. The rim 23 of thebracket 20 may be shaped corresponding to the back frame 110 of thesub-module 100, so that the back frame 110 of the sub-module 100 can befitted to the rim 23 of the bracket 20, thereby supporting thesub-module 100 on the bracket 20. In this state, the rear surface 111 ofthe back frame 110 may be disposed to face the surface 21 of the bracket20, and the circular edge of the rear surface 111 of the back frame 110is arranged along the rim 23 of the bracket 20.

A connector 25 electrically connecting with the power cable 10 may beprovided in a certain area on the surface 21 of the bracket 20. When thesub-module 100 is attached to the bracket 20, the connector 25 of thebracket 20 may be electrically connected to a connector 113 of thesub-module 100 provided in a certain area on the rear surface 111 of theback frame 110. The connectors 25 and 113 may include correspondingelectric terminals (e.g., male and female connectors) so that electriccurrent can flow through each other when they are connected. Thus, thesub-module 100 may receive power while being supported on the bracket20.

In this exemplary embodiment, the sub-module 100 may be supported on thebracket 20 in such a manner that the back frame 110 of the sub-module100 is fitted to the bracket 20. However, there are no limits to themanner of attachment. Alternatively, for example, the surface 21 of thebracket 20 may include a magnet. In this case, the back frame 110 may bemade of metal or another magnet so that the back frame 110 can besupported on the surface 21 of the bracket 20 by a magnetic force.

In other words, the structure by which the sub-module 100 is supportedon the installation surface and receives power is not limited to thestructure shown in FIG. 3.

FIG. 4 is a perspective view of another structure for mounting asub-module on an installation surface.

As shown in FIG. 4, a sub-module 400 may include elements such as a backframe 410. The basic structure of the sub-module 400 may besubstantially equivalent to the sub-module 100 according to theforegoing exemplary embodiment, and thus repetitive descriptions thereofwill be avoided.

The sub-module 400 in this exemplary embodiment is different from thesub-module 100 of the foregoing exemplary embodiment in the structurefor mounting onto the installation surface. Specifically, the sub-module400 has a sub-frame 420 protruding from a lower side of a back frame 410and having a predetermined shape. An electric plug 430 protrudes fromthe back of the sub-frame 420. As the electric plug 430 is connected toa plug socket of an external power source such as a wall socket foralternating current (AC), the sub-module 400 may attach itself securelyon the installation surface as well as receive power from the externalpower source.

Below, elements of a sub-module for processing the audio signal will bedescribed.

FIG. 5 is a block diagram of signal processing elements in a sub-module.

As shown in FIG. 5, the sub-module 100 may include the display 130, aloudspeaker 140 for generating sound, a microphone 150 for receiving avoice input, a communicator 160 for transmitting and receiving a signal,a storage 170 for storing data therein, and a signal processor 180 forprocessing a signal or data in accordance with predetermined processes.These elements of the sub-module 100 can have access to one anotherthrough a system bus, and thus they can interwork with one another.Among them, the communicator 160, the storage 170 and the signalprocessor 180 may be provided separately, or at least two of them may beintegrated as a system-on-chip (SoC).

The display 130 may be achieved by arranging a plurality of LEDs in theform of a matrix on a printed circuit board, and display simple textinformation by turning on/off each of the LEDs. The display 130 mayinclude the plurality of LEDs, and the printed circuit board, on whichwires for supplying power are printed.

The loudspeaker 140 may generate sound based on the audio signalprocessed by the signal processor 180. The loudspeaker 140 may includeunit loudspeakers corresponding to channels of the audio signal inaccordance with the supported channels. For example, the loudspeaker 140may include two left and right unit loudspeakers to support stereochannels, or may include three unit loudspeakers respectivelycorresponding to a left channel, a right channel and a center channel.

Besides generating sound, the loudspeaker 140 may emit ultrasonic wavesfor sensing the distance between the sub-module and a predeterminedobject. The ultrasonic waves output from the loudspeaker 140 collidewith a certain object, and the reflected waves caused by this collisionare collected by the microphone 150, thereby determining a distancebetween the sub-module 100 and the object. Use of this principle will bedescribed later.

The microphone 150 may collect sounds generated outside the sub-module100 and convert them into an audio signal. The audio signal may betransmitted to the signal processor 180. For example, the microphone 150may receive a user's speech and generate an audio signal correspondingto the speech. Of course, the sound collectable by the microphone 150 isnot limited to a user's speech. Alternatively, a sound made by anothersub-module may be collected.

The microphone 150 may collect not only sound corresponding to a user'saudible range but also reflected waves of ultrasonic waves. Further, themicrophone 150 may support beamforming. To this end, at least two unitmicrophones 150 may be provided in the sub-module 100. The microphone150 supporting the beamforming function is used to determine a user'srelative position with respect to the sub-module 100, details of whichwill be described later.

The communicator 160 may be provided as a communication module chipsetmounted on a printed circuit board. For convenience of easy attachmentof the sub-module 100 to the installation surface, the communicator 160may support wireless communication protocols such as wireless fidelity(Wi-Fi), Wi-Fi direct, Bluetooth, etc. In accordance with the wirelesscommunication protocols, the communicator 160 can communicate with notonly an electronic apparatus such as a television, a mobile device, ahub for Internet of Things, an access point, etc. but also with othersub-modules. In particular, the communicator 160 may support protocolspreviously approved for communication with other sub-modules of theaudio apparatus.

The storage 170 may store data processed by the signal processor 180.The storage 170 may include a flash memory, a hard disk drive, a solidstate drive or like nonvolatile memory. To make the sub-module 100lightweight and small, the storage 170 may be achieved by the flashmemory. The storage 170 may store an operating system, drivers,firmware, applications and like data to be executed for computation andoperations of the signal processor 180. Further, the storage 170 mayfurther include a random access memory (RAM) or like volatile memory sothat the data can be executed by the signal processor 180.

The signal processor 180 may be achieved by a hardware circuit such as achipset mounted on a printed circuit board, a central processing unit(CPU), a microcontroller or a system on chip (SoC). Fundamentally, thesignal processor 180 may perform various processes for operating thesub-module 100, such as setting for a relative position of anothersub-module, setting for a user's current position, control of thedisplay 130, etc. in addition to processing of an audio signal. Such aprocess may be performed when data stored in the nonvolatile memory ofthe storage 170 is loaded onto the volatile memory of the storage andthe signal processor 180 executes the loaded data.

Below, elements for the process of outputting an audio signal to theloudspeaker 140, among the processes of the signal processor 180, willbe described in brief. The elements to be described below are concernedwith the process of outputting the audio signal to the loudspeaker 140,but the signal processor 180 may further include additional elements forperforming other processes.

The signal processor 180 may include a digital signal supplier 181 foroutputting a digital signal of an audio signal, a pulse width modulation(PWM) processor 182 for outputting a PWM signal based on the digitalsignal output from the digital signal supplier 181 and an amplifier 183for amplifying the PWM signal from the PWM processor 182.

The digital signal supplier 181 modulates an input audio signal into adigital signal of a pulse code. To this end, the digital signal supplier181 includes a digital signal processing (DSP) chip, a Moving PictureExperts Group (MPEG) converter integrated circuit (IC), etc.

The PWM processor 182 converts a pulse code modulation signal, whichoutput from the digital signal supplier 181 and having a smallamplitude, into a low-power PWM signal.

The amplifier 183 employs a semiconductor switching device of aswitching circuit (e.g. a field effect transistor (FET)) to amplify thelow-power PWM signal output from the PWM processor 182 into a high-powerPWM signal. For example, the amplifier 183 may receive a low-power PWMsignal of about 3.3 V into a high-power PWM signal of about 5-40 V. Theamplifier 183 applies low-pass filtering to the amplified high-power PWMsignal and outputs the filtered signal to the loudspeaker 140.

The amplifier 183 includes an amplifying circuit and an LC filtercorresponding to the number of channels of the audio signal. Theamplifying circuit is an element for amplifying the input audio signal,and utilizes an FET. The LC filter, also known as a resonant circuit, isan element for filtering a signal of a certain frequency band, and usesan inductor and a capacitor.

The PWM processor 182 sends a PWM signal to each amplifying circuit ofthe amplifier 183. Each amplifying circuit amplifies the PWM signalindividually sent from the PWM processor 182, and each LC filter filtersthe amplified PWM signal with respect to a certain frequency band,thereby demodulating the PWM signal and outputting the demodulatedsignal to the loudspeaker 140. The loudspeaker 140 makes soundscorresponding to the channels of the audio signal.

With this structure, the processing operations of the sub-module 100 inthe audio apparatus 1 according to an exemplary embodiment will bedescribed.

FIG. 6 is a flowchart of controlling a sub-module in an audio apparatus.

As shown in FIG. 6, at operation S110, system power of the sub-module isturned on.

At operation S120, the sub-module determines whether settingsinformation of a voice field or a sound field is previously stored ornot. Details of the voice field will be described later.

If the settings information of the voice field has been previouslystored, at operation S130, the sub-module obtains the settingsinformation of the voice field.

On the other hand, if the settings information of the voice field hasnot been previously stored, at operation S140, the sub-module determinesrelative positions of other sub-modules in the audio apparatus. Here,the respective sub-modules may share their determination informationabout the positions with one another.

At operation S150, the sub-module sets the voice field of thesub-modules in the audio apparatus, based on information about thedetermined and shared positions.

At operation S160, the sub-module stores the obtained settingsinformation about the voice field.

When the settings information about the voice field is obtained, atoperation S170, the sub-module determines a user's current position withrespect to the sub-module in the voice field.

At operation S180, the sub-module adjusts an output level of a soundgenerated by the loudspeaker in accordance with a user's currentposition.

Thus, the audio apparatus may form the voice field by the plurality ofsub-modules, so that each sub-module can adjust the sound output statein accordance with a user's current position. Even when a user iscontinuously moving within the voice field, the sound output of eachsub-module may be adjusted in real time corresponding to the user'scurrent position. Thus, the audio apparatus according to an exemplaryembodiment provides a sound environment optimized for a user.

The voice field is an area formed by the plurality of sub-modules in theaudio apparatus (i.e. a range or a combination of ranges of the soundinput/output ranges of the sub-modules). In the case where threesub-modules constitute one set of the audio apparatus, the respectivesub-modules may be arranged to form a triangular shape, and the voicefield may refer to an area inside the triangle.

In practice, the range that the sound input/output of the sub-moduleswill reach is not only an area inside the triangular shape but also alarger area that surrounds the triangle. However, it is difficult tomeasure the precious range that the sound input/output of thesub-modules will reach, and therefore, it may be hard to clearlydemarcate such a range. Thus, the area inside the triangle will beregarded as the voice field in this illustration for convenience.

Below, the method of setting (i.e., determining) the voice field by thesub-module will be described.

FIG. 7 illustrates a voice field determined by the audio apparatus 1 viathe plurality of sub-modules 100, 200 and 300.

As shown in FIG. 7, the audio apparatus 1 may include three sub-modules100, 200 and 300. A voice field 500 may include a triangular area formedby the lines connecting the sub-modules 100, 200 and 300. To determinethe voice field 500, the lengths of the respective straight lines (i.e.the distances between three sub-modules 100, 200 and 300) have to bedetermined. Once the three distances are obtained, the voice field 500including the triangular area formed by sides corresponding to theobtained distances may be determined. The sub-modules 100, 200 and 300are respectively placed at the vertexes of the voice field 500.

There may be many different methods of calculating the distances betweenthe plurality of sub-modules 100, 200 and 300. For example, ultrasonicwaves may be used to measure the distances. Each loudspeaker of thesub-modules 100, 200 and 300 may not only generate sound having anaudible frequency of 16-20,000 Hz, but also generate ultrasonic waveshaving a frequency higher than 20 kHz.

For example, the first sub-module 100 include a pulse generator togenerate and emit the ultrasonic waves based on an inverse-piezoelectriceffect. The first sub-module 100 alternately applies positive andnegative voltages to an piezoelectric device for a short period of time,so that the piezoelectric device can alternate between deformation andrestoration. Vibrating energy generated by the alternation between thedeformation and restoration of the piezoelectric device is transformedinto the ultrasonic waves and emitted from the first sub-module 100.

When the ultrasonic waves from the first sub-module 100 reach the secondsub-module 200, the ultrasonic waves are reflected from and refracted bythe second sub-module 200. The reflected waves propagate from the secondsub-module 200 to the first sub-module 100.

When the first sub-module 100 receives the reflected waves, a vibratorof the first sub-module 100 generates voltage by the reflected wavesbased on a piezoelectric phenomenon. The generated voltage is measuredby a voltmeter.

By the same principle, the first sub-module 100 transmits the ultrasonicwaves and receives the reflected waves. Here, the first sub-module 100measures a distance between the first sub-module 100 and the secondsub-module 200 by measuring the time taken between the transmission andthe reception of the ultrasonic waves (i.e. time elapsed from the momentwhen the ultrasonic waves are transmitted to the moment when theultrasonic waves are returned from the second sub-module 200).

By the same principle, a distance between the first sub-module 100 andthe third sub-module 300, and a distance between the second sub-module200 and the third sub-module 300 may also be calculated. Because thefirst sub-module 100, the second sub-module 200 and the third sub-module300 can communicate with one another, three distance parameters may beshared among the three sub-modules 100, 200 and 300 by exchanging theircalculated distance information. For example, the second sub-module 200may calculate the distance between the second sub-module 200 and thethird sub-module 300, and transmit this information to the firstsub-module 100 and/or the third sub-module 300.

Thus, each of the sub-modules 100, 200 and 300 determines the range ofthe voice field 500, and determines the respective positions of thesub-modules 100, 200 and 300 within the voice field 500.

Below, a method of determining a user's position within the voice field500, which was determined and set as described above, will be described.

FIG. 8 illustrates a process of determining a user's position within avoice field by each of the sub-modules 100, 200 and 300 in the audioapparatus 1.

As shown in FIG. 8, the audio apparatus 1 may include three sub-modules100, 200 and 300, and the voice field 500 may be defined by lines 510,520 and 530 connecting the sub-modules 100, 200 and 300.

If a user U is positioned in a certain position on the voice field 500at a certain point of time, there are many ways of determining arelative position of the user U with respect to each of the sub-modules100, 200 and 300. For example, a distance between the user U and each ofthe sub-modules 100, 200 and 300 may be measured. Alternatively, anangle between the user U and each of the sub-modules 100, 200 and 300may be measured.

In the latter case, the relative angles between the user U and thesub-modules 100, 200 and 300 may be represented in various forms. Forexample, the relative angle may be given with respect to the sides ofthe voice field 500. The angle between the first sub-module 100 and theuser U may be given as ‘d1’ with respect to the side 510 of the voicefield 500, the angle between the second sub-module 200 and the user Umay be given as ‘d2’ with respect to the side 520 of the voice field500, and the angle between the third sub-module 300 and the user U maybe given as ‘d3’ with respect to the side 530 of the voice field 500.However, these relative angles are merely examples, and there are nolimits to the representations of the angles.

There may be many methods of measuring the relative angles between theuser U and the sub-modules 100, 200 and 300. For example, according to abeamforming technique, the direction from which a sound is coming may besensed by using an omnidirectional microphone. One microphone may not beenough to make use of the beamforming technique, and there may be a needof at least two microphones for respectively calculating a phasedifference between respectively received sounds. That is, each of thesub-modules 100, 200 and 300 may each include at least two microphones.

Specifically, if each of the sub-modules 100, 200 and 300 is outputtingits own sound, the first sub-module 100 may collect the output soundsthrough the microphones. The first sub-module 100 may receiveinformation about an audio signal output from the second sub-module 200and an audio signal output from the third sub-module 300.

The first sub-module 100 may analyze a waveform obtained by removing therespective audio signals of the sub-modules 100, 200 and 300 from theaudio signal of the sound received in the microphone, therebydetermining the relative angle d1 with respect to the position of theuser U. The analysis of the waveform may be achieved by various methodssuch as comparison with a predetermined profile, comparison between theamplitude of the waveform and a known threshold value.

Likewise, the second sub-module 200 and the third sub-module 300 cancalculate the angles d2 and d3 based on the foregoing principles. Bythis method, the sub-modules 100, 200 and 300 may determine relativepositions of the user U and control their respective sound output statesbased on the determined positions.

There may be various examples of the kinds of sound output states thatare used when each of the sub-modules 100, 200 and 300 controls thesound output state in accordance with the relative positions of a userU.

FIG. 9 illustrates the sub-modules 100, 200 and 300 in the audioapparatus 1 outputting sounds of a stereo channel in accordance with auser's position.

As shown in FIG. 9, if the user U is at a current position 550 withinthe voice field 500 formed by the plurality of sub-modules 100, 200 and300, the sub-modules 100, 200 and 300 may control the output states oftheir sounds in accordance with the current position 550. For example,if each of the sub-modules 100, 200 and 300 outputs sounds of audiosignals corresponding to a left channel, a center channel and a rightchannel, the sub-modules 100, 200 and 300 may be different from oneanother in a main output channel of the audio signals in accordance withthe current position 550 of the user U. Here, a main output channel maysignify that the channel is either output exclusively or that thechannel has a higher volume level than the other channels.

If it is determined that the current position 550 of the user U isclosest to the second sub-module 200 among the plurality of sub-modules100, 200 and 300, the second sub-module 200 may place a relativeemphasis on the sound of the center channel, and the first sub-module100 and the third sub-module 300 may respectively place an emphasis onthe sounds of the left and right channels, while outputting the sound.Here, the first sub-module 100 and the third sub-module 300 may outputthe sound of the left channel and the sound of the right channel withsubstantially the same amount of emphasis between the two.

If the user U has moved from a previous position 540 to the currentposition 550, the analysis may reveal that the user U is likely facingtoward the second sub-module 200 currently and observing the firstsub-module 100 on his left and the third sub-module 300 on his right. Inthis regard, the second sub-module 200 may place an emphasis onoutputting the sound of the center channel, while the first sub-module100 places an emphasis on outputting the sound of the left channel, andthe third sub-module 300 places an emphasis on outputting the sound ofthe right channel. In brief, the audio apparatus 1 may determine acurrent position and/or orientation of the user U based on the user'smovement history, and allow the channels of the sound output from eachof the sub-modules 100, 200 and 300 to be adjusted based on thedetermined position and/or orientation. Such a movement history of theuser U may be stored in each of the sub-modules 100, 200 and 300.

In this manner, each of the sub-modules 100, 200 and 300 in the audioapparatus 1 controls the output state of the sound in accordance withthe current position 550 of the user U.

In this embodiment, each of the sub-modules 100, 200 and 300 controlsthe output state of the sound in accordance with the position of theuser U, but the present disclosure is not limited thereto. For example,each of the sub-modules 100, 200 and 300 may control various operationmodes as well as the output state of the sound depending on the designof the audio apparatus 1.

FIG. 10 illustrates the sub-modules 100, 200 and 300 in the audioapparatus 1 respectively controlling their various operation modes inaccordance with a user's position.

As shown in FIG. 10, a current position of a user U is closer to thefirst sub-module 100 than to the second sub-module 200 or the thirdsub-module 300 within the voice field 500 formed by the plurality ofsub-modules 100, 200 and 300.

In this case, the first sub-module 100 may turn up a volume level of anoutput sound because the user U is relatively close to the firstsub-module 100. On the other hand, the second sub-module 200 and thethird sub-module 300 may turn down a volume level of an output soundbecause the user U is relatively distant from them.

However, the volume level of the sound does not have to be turned upwhen the user U gets closer to the corresponding sub-module. Forexample, the audio volume may be controlled inversely. That is, thefirst sub-module 100 may turn down the volume of the sound, while thesecond sub-module 200 and the third sub-module 300 may turn up theirrespective sound volumes.

If the user U is relatively closer to the first sub-module 100, the userU is likely to view or control the first sub-module 100 rather than thesecond sub-module 200 and the third sub-module 300. In this regard, thefirst sub-module 100 may turn on or turn up the LEDs, and the secondsub-module 200 and the third sub-module 300 turn off or dim the LEDs.Here, the LEDs refer to the respective indicator rings or the displaysof the sub-modules 100, 200 and 300.

Further, the first sub-module 100 may turn on or turn up the microphone,and the second sub-module 200 and the third sub-module 300 may turn offor turn down the microphone, when the user U approaches the firstsub-module 100.

As illustrated in these examples, the audio apparatus 1 may controlvarious operation modes of the sub-modules 100, 200 and 300 inaccordance with the relative positions of the user U with respect toeach of the sub-modules 100, 200 and 300.

Below, some of these operation modes of the sub-modules 100, 200 and 300will be described.

FIG. 11 is a block diagram illustrating a sound reproduction mode of thesub-module 100 in the audio apparatus 1.

As shown in FIG. 11, the sub-module 100 enters the sound reproductionmode (i.e., sound playback mode) in response to a certain event. Forexample, at operation S210, a predefined command may be input to thesub-module 100 through the microphone 150, and the sub-module 100 mayoperate in the sound reproduction mode.

At operation S220, the communicator 160 may receive audio data having apredetermined amount of data per unit time from the external apparatus,such as a mobile phone, a tablet computer, a desktop computer, etc., andtransmit the audio data to the signal processor 180. The amount of audiodata received at the communicator 160 per unit time may vary dependingon various factors such as a communication protocol supported by thecommunicator 160, the capacity of the storage 170, the processingcapabilities of the signal processor 180, etc.

At operation S230, the signal processor 180 may buffer (i.e. temporarilystore) the audio data from the communicator 160 in the storage 170. Theaudio data may be directly buffered from the communicator 160 to thestorage 170 without passing through the signal processor 180.

At operation S240, the signal processor 180 may obtain the audio databuffered in the storage 170, and at operation S250, the obtained audiodata may be processed. The processing of the audio data may, forexample, include extraction of metadata from the audio data, decoding ofthe audio data, amplification and volume control of the decoded audiodata, etc. In this process, the signal processor 180 may adjust theoutput state of the sound in accordance with a user's position asdescribed above.

At operation S260, the signal processor 180 may output the processedaudio data to the loudspeaker 140.

In addition, at operation S270, the signal processor 180 may display themeta information (i.e., metadata) on the display 130. The metainformation may include various types of information about the audiodata. For example, if the audio data is represents a song, the metainformation may include a title, an artist, a release date, albuminformation including a song listing, etc.

Here, the signal processor 180 may selectively process the metainformation to be displayed in accordance with predefined conditions.For example, the meta information may be displayed when the voicerecognition mode of the sub-module 100 is activated, but the metainformation may be not displayed when the voice recognition mode of thesub-module 100 is deactivated.

Thus, if the sub-module 100 outputs a sound in the sound reproductionmode, the sub-module 100 may provide two kinds of interfaces forallowing a user to control the output state of the sound. For example, afirst user interface may be provided when the voice recognition mode ofthe sub-module 100 is deactivated, and may enable a user to control thesub-module 100 by directly manipulating the dial provided in thesub-module 100. Additionally, a second user interface may be providedwhen the voice recognition mode of the sub-module 100 is activated, andmay enable a user to control the sub-module 100 by user's voice.

Below, a user's manipulation of the voice recognition mode of thesub-module 100 will be described.

FIG. 12 is a perspective view of the back frame 110 of the sub-module100 in the audio apparatus.

As shown in FIG. 12, the sub-module 100 may include the back frame 110,the front frame 120, the display 130 recognizable by a user through thesurface 121 of the front frame 120, and the toggle button 125 providedin a lower portion on the surface 121 of the front frame 120.

The toggle button 125 may be toggled by a user to activate or deactivatethe voice recognition mode of the sub-module 100. If the voicerecognition mode is deactivated by the toggle button 125, a user mayperform manipulation by directly turning the back frame 110 or the frontframe 120 having the dial structure of the sub-module 100.

As a user turns the back frame 110, the sub-module 100 may, for example,control the volume of the output sound. Further, the sub-module 100 maydisplay information about the controlled volume while controlling thesound volume.

The operation of the sub-module 100 in response to a user's manipulationof turning the back frame 110 or the front frame 120 may be performed inconnection with the activation of the voice recognition mode of thesub-module 100 or regardless of the activation of the voice recognitionmode of the sub-module 100.

In the former case, the sub-module 100 operates in response to therotation of the back frame 110 or the front frame 120 when the voicerecognition mode is activated, but does not operate in response to therotation of the back frame 110 or the front frame 120 when the voicerecognition mode is deactivated. In the latter case, the sub-module 100operates in response to the rotation of the back frame 110 or the frontframe 120 regardless of the activation of the voice recognition mode.

FIG. 13 is a perspective view of the front frame 120 of the sub-module100 in the audio apparatus being manipulated by a user.

As shown in FIG. 13, the sub-module 100 may switch between categories orchannels of audio data currently being reproduced, in response to a userturning the front frame 120. For example, the sub-module 100 may switchto a first category of the currently reproduced audio data into a secondcategory, and reproduce audio data of the second category. If, forexample, a plurality of audio data files belong to the second category,the audio data files may be selected in a predefined order.

If a plurality of audio data files belong to the second category, thereare various ways of selecting the file to be switched and reproduced.One example is to always select the first file when the audio data filesin the second category are sorted in a predetermined order according tovarious parameters. Here, the parameter may, for example, include a filename, a file modified time, a file generated time, or an artist name ifthe audio data is related to music.

Another example is to select the last reproduced (i.e., last played)file when the audio data files of the second category are sorted in apredetermined order. In this case, a use history has to be stored andaccessed by the sub-module 100. The use history may be stored in thesub-module 100, or in an external apparatus from which the sub-module100 receives the audio data.

Below, a principle of switching the category of the audio data fileswill be described.

FIG. 14 is a block diagram illustrating a process of switching amongcategories of audio data received from an external apparatus 30.

As shown in FIG. 14, the external apparatus 30 may store the audio datafiles according to the plurality of categories. The sub-module 100 maycommunicate with the external apparatus 30 and receive the audio datafiles from the external apparatus 30 in the sound reproduction mode.

At operation S310, the sub-module 100 may receive a user's instructionfor sound reproduction.

At operation S320, the sub-module 100 may access a use history 610(i.e., playback history), and send a request for a file A01 of CategoryA indicated by the use history 610 to the external apparatus 30. The usehistory 610 may be stored in the sub-module 100, the external apparatus30 or another separate apparatus.

At operation S330, the external apparatus 30 may transmit the file A01of Category A among the plurality of previously stored categories to thesub-module 100 in response to the request from the sub-module 100. Thus,the sub-module 100 may reproduce the file A01 of Category A.

In this embodiment, the sub-module 100 sends to the external apparatus30 a request for one file, and the external apparatus 30 transmits theone file corresponding to the request to the sub-module 100. However,the disclosure is not limited to such a 1:1 correspondence.Alternatively, 1:N correspondence, N:1 correspondence, N:Ncorrespondence, etc. are also possible. Here, N is a positive integer.For example, when the sub-module 100 makes a request for the file A01 ofCategory A, the external apparatus 30 may transmit the file A01 togetherwith a predetermined number of subsequent files within Category A to thesub-module 100 in accordance with 1:N correspondence.

At operation S340, the sub-module 100 may receive a user's instructionfor switching the current category from A to B. Such a switchinginstruction may be carried out as described above with reference to FIG.13.

At operation S350 the sub-module 100 calls the use history 610, checksthe last reproduced file B02 among the audio data files within thecategory B, and makes a request for the file B02 of the category B tothe external apparatus 30.

At operation S360, the external apparatus 30 may select Category Binstead of Category A in response to the request from the sub-module100, and transmit the file B02 of Category B to the sub-module 100.

Consequently, the sub-module 100 may reproduce the file B02.

In addition, the sub-module 100 may recognize a user's speech inputthrough the microphone while the voice recognition mode is activated,and thus operate based on a command corresponding to the recognizedspeech. In the voice recognition mode, the sub-module 100 may recognizea user's speech and is therefore capable of supporting various functionsmore complex or specific than when a more limited input method is used,such as manipulating dials. Under the voice recognition mode, thefunctions supported by the sub-module 100 may include making a phonecall using the mobile phone, controlling another device through a hub,etc.

Below, an exemplary embodiment, in which the sub-module 100 accesses amobile phone and sends a message to another mobile phone, will bedescribed.

FIG. 15 is a sequence diagram illustrating a method of the sub-module100 in the audio apparatus 1 sending a message through a mobile phone700.

As shown in FIG. 15, at operation S410, the sub-module 100 may performpairing to communicate with the mobile phone 700.

At operation S420, the sub-module 100 may receive a message sendingpreparation instruction from a user U. The message sending preparationinstruction may be input to the sub-module 100 by a speech of the userU, and may include information for specifying a target to which amessage will be sent. This information may, for example, include a name,a nickname, etc. stored corresponding to a phone number registered to amobile phone 700.

At operation S430, the sub-module 100 may acquire contact information ofa target specified by the message sending preparation instruction fromthe mobile phone 700. For example, the sub-module 100 acquires phonenumbers of the people stored in the mobile phone 700, and retrieves aphone number of the target, specified by the message sending preparationinstruction, among the phone numbers.

At operation S440, the sub-module 100 may display the acquired contactinformation. Thus, a user can confirm whether the sub-module 100correctly identified the target specified by the message sendingpreparation instruction.

At operation S450, the sub-module 100 may receive a message input fromthe user U. The message input is for receiving the content of themessage to be sent to the phone number specified by the message sendingpreparation instruction. In this embodiment, the message is input to thesub-module 100 via speech recognition based on the user U's speech.

At operation S460, the sub-module 100 may send the message to the mobilephone 700.

At operation S470, the mobile phone 700 may send the received message tothe corresponding phone number. The message may be sent via, forexample, short message service (SMS), instant messaging, email, etc.

Thus, the sub-module 100 may send a message input based on a user'svoice via the mobile phone 700.

Below, an embodiment where the sub-module 100 accesses a mobile phoneand sends a message to another mobile phone will be described.

FIG. 16 is a sequence diagram illustrating a method of the sub-module100 in the audio apparatus 1 making a phone call through the mobilephone.

As shown in FIG. 16, at operation S510, the sub-module 100 may performparing with the mobile phone 700.

At operation S520, the sub-module 100 may receive a target selectinginstruction from a user U. The target selecting instruction includesinformation for specifying a target, to which the sub-module 100 makes aphone call through the mobile phone 700. The target selectinginstruction may be input to the sub-module 100 by a speech of a user U.

At operation S530, the sub-module 100 may acquire contact information ofa target specified by the target selecting instruction, and at operationS540, the sub-module 100 may display the acquired information.

If the user U confirms the displayed information at operation S550, thesub-module 100 may send a dialing instruction for the target to themobile phone 700 at operation S560.

At operation S570, the mobile phone 700 may begin dialing for the targetin response to the dialing instruction. During the operation S570, thesub-module 100 may display a message that the dialing is beingperformed.

If the mobile phone 700 connects with the target, at operation S580, themobile phone may receive an audio signal from the target mobile phoneand transmit the audio signal to the sub-module 100, thereby outputtinga sound of the audio signal through the loudspeaker of the sub-module100. Further, at operation S590, the mobile phone 700 may transmit anaudio signal received from the sub-module 100 to the target mobilephone.

Thus, the sub-module 100 may make a phone call to another mobile phonethrough the mobile phone 700 in response to a voice instruction of auser U.

Below, an exemplary embodiment, where the sub-module 100 controlsanother external device through a hub based on Internet of Things (IoT),will be described.

FIG. 17 illustrates a process of the sub-module 100 in the audioapparatus 1 controlling an external device 720 through a hub 710.

As shown in FIG. 17, the sub-module 100 may be provided to control theexternal device 720 through the hub 710. The hub 710 may group thesub-module 100, the external device 720, and other devices (e.g.,devices found in the same network based on a common protocol).

Here, the common protocol is as follows. To group a plurality of“things” (i.e., electronic devices) in the network, the things need tobe capable of not only communicating with each other but alsorecognizing and processing a command exchanged between them. To thisend, things within a network need to operate on a common or compatibleapplication or platform. For example, a thing on a transmission side,which operates on a certain platform, may transmit a signal to a thingon a receiving side through a hub. In this case, if the thing on thereceiving side operates on the platform in common with the thing on thetransmitting side, it can recognize and process the received signal.Likewise, if a plurality of things are operating on the common orcompatible application or platform, the respective things are regardedas though they are operating based on a common protocol.

The things may include a television; an electronic picture frame andlike display apparatus capable of displaying an image; a set-top box andlike image processing apparatus capable of processing a video signalwithout directly displaying an image; home appliances such as a washingmachine, a refrigerator, an air conditioner and the like; officeequipment such as a printer, a copying machine, a scanner and the like;and other devices such as a light bulb, an electric heater and the like.Further, the things may include various wearable devices or mobiledevices mounted with a sensor.

For example, the external device 720 may be a water heater, and a usermay set a temperature of the water heater. In this case, for example, ifthe user may utters a voice command, “set temperature to 70 degrees,”the sub-module 100 may recognize and analyze the user's speech. Inaccordance with the analysis results, the sub-module 100 may deduce atarget and an instruction based on the user's speech. In this example,the sub-module 100 may deduce from the user's speech that the target isthe external device 720 (i.e., the water heater) and the instruction isto set the temperature to 70 degrees Celsius.

The sub-module 100 may issue a command to the external device 720through the hub 710 for adjusting the temperature to 70 degrees.

The external device 720 may interpret the command received from thesub-module 100 through the hub 710, and adjust the temperature to 70degrees in response to the command. Then, the external device 720 maysend to the sub-module 100 a response indicating that the instructionwas performed successfully, through the hub 710.

The sub-module 100 may display a message 630 indicating that thetemperature is set to 70 degrees based on the response received from theexternal device 720.

Thus, the sub-module 100 can control the operations of the externaldevice 720 based on the Internet of Things (IoT) technology in themanner described above.

The methods according to the foregoing exemplary embodiments may beachieved in the form of a program command or instructions that can beimplemented in various computers, and recorded in a computer-readablemedium. Such a computer-readable medium may include a program command, adata file, a data structure or the like, or a combination thereof. Forexample, the computer-readable medium may be a nonvolatile storage, suchas a read-only memory (ROM) or the like, regardless of whether thestorage is erasable or rewritable. For example, the computer-readablemedium may be a RAM, a memory chip, a device or integrated circuit(IC)-like memory, an optically or magnetically recordable ormachine-readable storage medium such as a compact disc (CD), a digitalversatile disc (DVD), a magnetic disk, a hard disk drive, a solid-statedrive, a magnetic tape or the like. It will be appreciated that amemory, which can be included in a mobile terminal, is an example of themachine-readable storage medium suitable for storing a program havinginstructions for materializing the exemplary embodiments. The programcommand recorded in this storage medium may be specially designed andconfigured according to the exemplary embodiments, or may be publiclyknown and available to those skilled in the art of computer software.

Although a few exemplary embodiments have been shown and described, itwill be appreciated by those skilled in the art that changes may be madein these exemplary embodiments without departing from the principles andspirit of the invention, the scope of which is defined in the appendedclaims and their equivalents.

What is claimed is:
 1. An audio apparatus comprising: a plurality ofsub-modules placed at locations separate from one another, eachsub-module of the plurality of sub-modules comprising a loudspeakerconfigured to generate sound and a communicator configured to performcommunication, wherein a first sub-module among the plurality ofsub-modules further comprises a processor configured to: process anaudio signal to be output as sound through the loudspeaker of the firstsub-module, determine a position of a user with respect to eachsub-module of the plurality of sub-modules, and change a state of thesound being output from the loudspeaker of the first sub-module inaccordance with the determined position of the user.
 2. The audioapparatus according to claim 1, wherein the processor is furtherconfigured to define an area corresponding to positions of the pluralityof sub-modules based on distances between the plurality of sub-modules,and determine the position of the user with respect to the defined area.3. The audio apparatus according to claim 2, wherein the firstsub-module further comprises a microphone configured to receive a soundinput, and wherein the processor is further configured to determine adistance between the first sub-module and a second sub-module among theplurality of sub-modules, based on a time taken by an ultrasonic wave tobe output from the loudspeaker of the first sub-module, reflected fromthe second sub-module, and received by the microphone of the firstsub-module.
 4. The audio apparatus according to claim 3, wherein theprocessor is further configured to receive information about a distancebetween the second sub-module and a third sub-module among the pluralityof sub-modules, from one of the second sub-module and the thirdsub-module through the communicator of the first sub-module.
 5. Theaudio apparatus according to claim 2, wherein the processor is furtherconfigured to determine the position of the user by determining an angleof the user with respect to each sub-module of the plurality ofsub-modules within the defined area.
 6. The audio apparatus according toclaim 5, wherein the first sub-module comprises at least two microphonesconfigured to receive sounds, and wherein the processor is furtherconfigured to determine the position of the user based on a phasedifference between the sounds respectively received by the at least twomicrophones.
 7. The audio apparatus according to claim 1, wherein theprocessor is further configured to select a channel of a plurality ofchannels within the audio signal, the selected channel corresponding tothe determined position of the user, and control a volume level of theselected channel to be different from volume levels of remainingchannels of the plurality of channels.
 8. The audio apparatus accordingto claim 1, wherein the processor is further configured to control avolume level of the sound being output through the loudspeaker inaccordance with the determined position of the user.
 9. The audioapparatus according to claim 1, wherein the first sub-module furthercomprises a display configured to display information related to theaudio signal, and a microphone configured to receive a sound input, andwherein the processor is further configured to activate the display andthe microphone in response to the determined position of the user beingcloser to the first sub-module than to the second sub-module, anddeactivate at least one of the display and the microphone in response tothe determined position of the user being closer to the secondsub-module than to the first sub-module.
 10. The audio apparatusaccording to claim 1, wherein the first sub-module further comprises amicrophone configured to receive speech from the user, and wherein theprocessor is further configured to retrieve contact information of acall recipient specified by the speech from a mobile phone connectablewith the communicator of the first sub-module, and dial the callrecipient through the mobile phone.
 11. A non-transitorycomputer-readable medium of an audio apparatus comprising a plurality ofsub-modules placed at separate locations from one another, thenon-transitory computer-readable medium storing program code for amethod to be executed by a processor of a first sub-module among theplurality of sub-modules, the method comprising: processing an audiosignal to be output as sound through a loudspeaker of the firstsub-module; determining a position of a user with respect to eachsub-module of the plurality of sub-modules; and changing a state of thesound being output from the loudspeaker of the first sub-module inaccordance with the determined position of the user.
 12. Thenon-transitory computer-readable medium according to claim 11, whereinthe determining the position of the user with respect to each sub-moduleof the plurality of sub-modules comprises: defining an areacorresponding to positions of the plurality of sub-modules based ondistances between the plurality of sub-modules; and determining theposition of the user with respect to the defined area.
 13. Thenon-transitory computer-readable medium according to claim 12, whereinthe defining the area corresponding to the positions of the plurality ofsub-modules comprises: determining a distance between the firstsub-module and a second sub-module among the plurality of sub-modules,based on a time taken by an ultrasonic wave to be output from theloudspeaker of the first sub-module, reflected from the secondsub-module, and received by a microphone of the first sub-module. 14.The non-transitory computer-readable medium according to claim 13,wherein the defining the area corresponding to the positions of theplurality of sub-modules comprises: receiving information about adistance between the second sub-module and a third sub-module among theplurality of sub-modules, from one of the second sub-module and thethird sub-module through a communicator of the first sub-module.
 15. Thenon-transitory computer-readable medium according to claim 12, whereinthe determining the position of the user with respect to the definedarea comprises: determining the position of the user by determining anangle of the user with respect to each sub-module of the plurality ofsub-modules within the defined area.
 16. The non-transitorycomputer-readable medium according to claim 15, wherein the determiningthe user's position by determining the angle of the user with respect toeach sub-module comprises: determining the position of the user based ona phase difference between sounds respectively received by at least twomicrophones of the first sub-module.
 17. The non-transitorycomputer-readable medium according to claim 11, wherein the changing thestate of the sound being output comprises: selecting one channel of aplurality of channels within the audio signal, the selected channelcorresponding to the determined position of the user; and controlling avolume level of the selected channel to be different from volume levelsof remaining channels of the plurality of channels.
 18. Thenon-transitory computer-readable medium according to claim 11, whereinthe changing the state of the sound being output comprises: controllinga volume level of the sound in accordance with the determined positionof the user.
 19. The non-transitory computer-readable medium accordingto claim 11, wherein the first sub-module comprises a display configuredto display information related to the audio signal, and a microphoneconfigured to receive a sound input, and wherein the method furthercomprises: activating the display and the microphone in response to thedetermined position of the user being closer to the first sub-modulethan to the second sub-module; and deactivating at least one of thedisplay and the microphone in response to the determined position of theuser being closer to the second sub-module than to the first sub-module.20. The non-transitory computer-readable medium according to claim 11,wherein the method further comprises: connecting with a mobile phone;retrieving, from the mobile phone, contact information of a callrecipient specified by a speech being input by the user through amicrophone of the first sub-module; and dialing the call recipientthrough the mobile phone.